Re: Suspicious warning in W64 build

[Richard Copley]

On 9 September 2017 at 08:33, Eli Zaretskii <address@hidden> wrote:
>> From: Richard Copley <address@hidden>
>> Date: Fri, 8 Sep 2017 22:08:04 +0100
>> Cc: Paul Eggert <address@hidden>, Angelo Graziosi <address@hidden>,
>>       Emacs Development <address@hidden>
>>
>> >> Would you mind also suppressing warnings from find-file-noselect
>> >> when called from autoload-find-generated-file, please, if you don't
>> >> object?
>> >
>> > Sorry, I'm not sure that's the right solution in that case.  We should
>> > try to understand why the problem happens in the first place.  E.g., I
>> > don't see it here (but I don't use MinGW64 or MSYS2).
>>
>> Seriously (not being rude)?
>
> Yes, seriously.  You'd expect that much of me, won't you?

Yes Eli.

>> It seems a lot of work for not much benefit.
>
> Not IME.  I frequently find that the real root cause of such obscure
> problems is something altogether unexpected, and sometimes it's the
> tip of an iceberg.  So I generally find looking into the root causes
> of such problems beneficial.
>
>> That conversion happens often, e.g., in normalize_filename.
>
> What conversion is that?

The down-casing of the drive letter in a native or MSYS file name.

>> And it's unlikely a warning from find_file_noselect there is ever
>> going to be helpful in catching a new bug.
>
> You may be right.  But we will only know for sure when we have
> understood the root cause.  It could very well be that there is indeed
> a bug, and this warning has already caught it, except that it went
> unnoticed until now, because it was never reported before.
>
> For starters, can you or Angelo tell where did that upper-case "C:/"
> originate from?

You can see the warnings, for example, by invoking configure by
absolute file name with an upper-case drive letter before running make.

Usually one uses a relative path and the problem can't arise.

I used to see this when I used a complicated Perl script to build
Emacs. The upper-case drive letter was just an artifact. It was
derived from the current directory of the calling command prompt.

> Also, are there other places in the build process
> that display file names with the upper-case drive letter?

Yes. Transcript attached.

> Thanks.

Thanks.

build.log.gz
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